disturbance

Population Studies of Isolated Nothofagus fusca Stands in the Lower Otira Valley, South Island, New Zealand

Population size and structure of 52 isolated Nothofagus fusca stands were investigated in the lower Otira Valley, 3-6 km from a major population centre in the upper Taramakau catchment. The approximate age of N. fusca pioneer trees, estimated from partial increment cores and calculations based on diameter growth rates, indicated that nearly all isolated stands originated after 1600 AD, predominantly during the periods 1600-1760 AD and 1865-1910 AD.

Life histories, dispersal, invasions, and global change: progress and prospects in New Zealand ecology, 1989–2029

We highlight three areas of significant progress in ecology since 1989 which are particularly relevant to New Zealand, and three major challenges for the next two decades. Progress: (1) The unusual life histories of New Zealand organisms, including extreme longevity and low reproductive rates, are now seen as efficient responses to the low-disturbance environment present before the arrival of large mammals, including humans.

The impact of trout on galaxiid fishes in New Zealand

Compared with the effect of invaders on the native terrestrial fauna of New Zealand, interactions between native fishes and introduced trout (sports fish in the genera Salmo, Oncorhynchus and Salvelinus) are less well known and there have been fewer efforts to remedy their effects. Trout have caused widespread reductions in the distribution and abundance of native galaxiid fishes, a family dominated by threatened species.

Recovery of a sooty shearwater (Puffinus griseus) breeding area after habitat destruction

We describe the recovery of an 88-m² area of sooty shearwater breeding habitat on Northeast Island, The Snares, New Zealand, during the eight breeding seasons after it was completely destroyed by excavation in December 1996. Burrow entrance density did not differ between the destroyed site and three comparison sites one year after the event. We detected breeding attempts of shearwaters in the season following disturbance, but burrow occupant density recovered more slowly, perhaps because the overall population density was declining over the same period.

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